Automatic choke for guns



sept. 7, 1937.

w. M. JUNG 2,092,649

AUTOMATIC CHOKE FOR GUNS Filed Junds, 193s 2 sheets-sheet 1 '//4w;`.\.v'//////////// 3 a n l la INVEN-ron IWALTER M. JUNG ATTORNEYSSept. 7, 1937. W, M JUNG 2,092,649

AUTOMATIC CHOKE FOR GUNS Filed June 6, 1936 2 Sheets-Sheet 2 INVENTORwALTEn M.J Ne

Patented Sept. 7, 1937 am Fri AUTOMATIC cnoxa Fon ctms Y waiter M. Jung,sans centre, Minn. Application :une c. 19st, serial No. 83,946

This invention relates to new and useful improvements in chokes forguns, and more particularly to a choke which is so constructed that itautomatically shifts from one position to lanother by the recoil of thegun, when the latter is iired.

An object of the invention is to provide a slmple and inexpensive chokefor a gun which may readily be applied to a conventional gun barrel atsmall cost, whereby the choke of the barrel may be varied, as desired.

A further object is to providean automatic choke for a gun which isadapted to be actuated by the recoil of thegun, whereby .the device willautomatically shift from non-choketo choke position, when the gun isinitially fired. assuming. of course, that the device has previouslybeen moved to its non-choke position.

Other objects of the invention reside in the simple and-inexpensiveconstruction of the device, whereby it may be manufactured at small costand is extremely simpleto operate; in the provision oi a novel deviceadapted to be applied to a gun barrel whereby the first shot iired fromthe gun will be through an open or non-choke barrel, and succeedingshots will be through a modified or full choke barrel; in the uniqueconstruction of the device which comprises a plurality of relativelysmall elements yloosely mounted in suitable apertures provided in thewall of the gun barrel, and which elements are normally concealed by a.member mounted for relative move@ ment onf the barrel, and whichoperates to actuate said elements to move Ithem into choke positionswithin the bore of the gun barrel, when said member is moved in onedirection; andfin the provision of a device having means for tempo`rarily retaining it in non-choke position. which retaining means isrendered ineffective to hold said device in non-choke position, when thegun is initially ilred, whereby the device automatically returns to itschoke position, so that following shots iired from the gunmay be througha modified or full choke barrel.

Other objects of the invention will appear from the followingdescription and accompanying drawings and `will be pointed out in theannexed claims.

In the accompanying drawings there has been disclosed a structuredesigned to carry out the various objects of the invention, but it is tobe understood that the linvention is not conned to the exact. lfeaturesshown as various changes may be made within the scope of the claimswhich follow. i

In the drawings:

Figure 1 is a top view of a portion oi' a gun barrel showing the devicemounted thereon;

Figure 2 is an end view oi Figure 1;

Figure 3 is a longitudinal sectional view show- 5 ing the generalconstruction of the device and showing it in non-choke position;

Figure 4 is a cross-sectional -view on the line 4-4 of4 Figure 3; l

Figure 5 is a view similar to Figure 3, but show- 10 y ing the device inchoke position;

Figure 6 is a cross-sectional view on the line 6-6 of Figure 5, showingthe elements projected into the bore of the barrel;

Figure 7 is a detail View showing the device 15 with the qmovable memberdetached therefrom;

Figure 8 is a detail sectional view on the line @-3 of Figure 6, showingthe spring means for temporarily retaining the movable member innon-choke position;

Figure 9 is aview showing a device of slightly modiiied construction;

Figure 10 is a longitudinal sectional view of the form shown in Figure9, illustrating the general commotion' thereof;

Figure 11 is a view similar to Figure 10, showing the inwardly movableelements in non-choke position;

Figure 12 is a view similar to`Figure 11, but showing the movable memberpositioned to inwardly move the elements. whereby their terminals aredisposed withinthe bore ot the barrel to provide a choke therefor;

'Figure 13 is a cross-sectional view of Figure 12, showing the elementsin operative positions with their terminals projecting into the bore ofthe barrel.

Figure 14 is a detail sectional view on the line id it of Figure 13,'showing the means provided for holding the movable member in non-choke40 position;

Figure 15 is a cross-sectional view showing a modified constructionwherein spherical elements are supported in apertures in the wall of thebarrel, and are adapted to be partially projected .into the bore toprovide a choke for the barrel:

and

Figure 18 is a view similar to Figure 1.' showing the device locked innon-choke position.

In the selected embodiment of the invention here shown, there i'sillustrated in Figure 1, a portion of a gun barrel, generally indicatedby the numeral 2, shown having an enlarged portion 3 which may be formedby suitably securing a cylindrical sleeve to the barrel as. for example.5f

ter from accumulating within the device, and whereby the device isrendered tantially selicleaning.

'EineA enlarged perdon t is shown provided with aplurality of elongatedi.; .u or apertures t which communicate with the bore of the relforwardly 'withoutf d, as best shown in .i 5. The end am oi theapertures d taper inwardly, whereby the bottoms of said apertures aresmaller than their outer or upper portions. A plurality 'or relativelysmall elements t are supported in the apertures t and are of such sizethat they cannot pass completely through the restricted` inner ends othe apertures, but whereby they may be projected into the bore of thegun barrel, as clearly illustrated in Figures 5 and 6, thereby toprovide a choke for the barrel. vWhen the elements which preferably aredisk-like in shape, are positioned as shown in Figures 5 and 6, and thegun is fired, the sealing wad, (not shown), immediately following thecharge of shot, will engage the inwardly protruding portion or theelements whereby its forward movement will be temporarily retarded. Suchretardation of the g wad will cause the column of shot to be projectedmaterially spreading, as it air, with the result that a ull choke shotpattern is obtravels through relatively small or l Means is providod fortemporarily locking or securing the elements in their operative chokepositions, as shown in Figures 5 and 6, and consists of a member l,shown mounted for relative sliding movement on the l and concealing theelements t, as Ebest illustrated in Figure 5. One end of.; the member lis bored to dt 'the periphery oi the enlarged portion 8 of the barrel,which thus provides a guide therefor. The opposite end ofthe member lhas a portion d bored to ilt the outside diameter of the barrel 2,whereby it is guidingly supported thereon.

'I'he member 1 is counter-bored as shown at t in Figures 3 and 5toreceivev a spring il, one end of which is seated against the shoulder i2provided by the portion 8 of the member 1, and the opposite end of whichis shown seated against the adjacentend of the enlarged portion 8. Thespring il therefore constantly urges .the member 'i in a left handdirection, when viewed as shown in Figures 3 and 5. thereby to move themember into full choke position. y y

In the formv of the invention, as shown in Figures 1 to 8, inclusive,thebore of the member which ilts the outside diameter of the enlargedportion 3 of the gun barrel, acts as a cam tace to secure or lock theelements d in choke position, ,as is clearly illustrated in LFigure 5.When the member 'I is movedto the position shown in Figure 3, theelements t will be alined with the counter-bore 9. which is oi suchdiameter that said elements may move outwardly sumciently to clear thebore oi the barrel, as best illustrated in Figure 4, thereby to providean open barrel,

In some instances, it may be desirable to use a modified choke, and toaccomplish this, I have provided an inediate cam surface i3 which, whenalined with the elements t, will cause them to be projected onlyslightly into the bore oi the en thus is' provided.

a usual sight it is shown provided at the end of the el and, in thepresent instance, has a dual function in that it provides a` sight gauge5 and alec a stop for the me i of the attachment. A suitable slot oropening, generally india cated by the numeral it, is provided in thewall of the :aber l and for.: an elongated portionl it and a relativelyshorter rtion il, separated 10 by an rig:- projecting notched portionit, which has a notch 2d, as bw shown in Figures l d i6. en the member iis in the tion shown inFigure l, it is in non-choke position, but

. when thrust forwardly to the position shown in 15 e 5, wherein theright hand end of the elongated portion d of the slot i5 engages thesight gauge id, the attachment will be in full choke position.-

When it is d red to use a modied choke, the 2o member is slightlyrotated upon the gun barrel until the sight gauge id enters therelatively shorter portion i'l oi the slot, or opening it, therebylimiting the forward movement of the member 'i upon the gun barrel sothat the inter- 25 mediate cam face or portion i3 of the member` l isalined with the elements thereby to provide a modified choke for thebarrel.

Should it be desired to lock the device in open barrel or non-chokeposition, the member l is 30 rotated to aline the notch 2l) thereof withthe sight gauge id, whereby the member 'i is locked against longitudinalmovement upon the barrel, and cannot accidentally, change its positionwhen the gun is in use. 35

Means is provided for temporarily locking or securing the member 4'I ofthe attachment in nonchoke position, and as shown in Figures 3 and 8,comprises a spring-actuated detent it, having one end suitably securedto the member l, and its free end projecting inwardly through an openingA in a wall of the member l, whereby the terminal thereof may bereceived in a socket 2i provided in the enlarged portion 3 of thebarrel, as best illustrated in Figure s. The tension in the detent w i8is such that it normally assumes the position shown in Figure 8, wherebyit is to be noted that the terminal thereof is disengaged from thesocket 2l of the portion t. An additional socket 22 is provided in theperiphery oi the portion 3, 50 as shown in Figure '1, adapted to receivethe terminal of the spring element or detent It, when the member 'i isrelatively rotated to cause the sight gauge or stop pin to be receivedin the portion l1 of the slot l5. An intermediate socket 55 3d may alsobe provided in the enlarged portion 3 of the barrel adapted to receivethe detent it, when the member 'i is positioned in non-choke position,as shown in Figure 16.

In the operation of the attachment, illustrated 60 in Figures 1 to 8, ifit is desired to use an open barrel for the iirst or initial shot redfrom the gun, the member 'i will be moved backwardly against the tensionof the spring il, by grasping it with the fingers and at the same timepressing the detent i8 inwardly. When the member l `reaches the tionshown in Figure 3, the termove completely out of the bore of the barrel,

'whereby an open barrel is provided.

the recoil of the gun will relieve the frictional' engagement of thedetent il with the front wall of the socket 2i, whereby the tension inthe detent i8 will causeit to move outwardly to the' position shown inFigure 8, whereby the spring i I will thrust the member ,1' forwardlyupon the gun barrel t'o the position shown in Figure 5. Such movement ofthe member 1 will automatically change the bore of the gun from an opento a modied oriull choke, without any action on the part'of the person-handling the gun. Follow-- ing shots fired from the barrel will bethrough a 'Y modified or full choke'barrel; until the member 1* f -isagain manually reset.

If it is desired to use a modified choke, the member 1 is rotated tomove thesight gauge or stop pin il into the portion i1 of the slot i5,whereby the forward movement of tlie member 1 is limited so that itcannot move into full choke position.

The portion 8 of. the member 1, which fits the outer diameter of thebarrel is shown provided with a plurality of air circulatingpassages 23,and suitable aircirculating passages 24 are also shown provided in thewall of the member 1. The circulating passages 23 and 24, and thegrooves 4 permit a portion of the gases to circulate through the device,when the gun is fired, thereby pre-- venting foreign matter fromaccumulating in the device. The exterior of the member 'i is preferablylkriurled as shown in Figure 1 tofaciiitate rotating it.

Figures 9 to i4, inclusive, illustrate a rhodiiedv construction whereinspaced sleeves 25 and 28 are shown .secured to the barrel 2, and havemounted thereon a member 21corresponding to the member 1 in the previousilgures; The member 2l is shown provided at its front end with arestricted portion 28 which substantially fits the exterior diameter ofthe barrel and provides a seat for one end of a spring 29, the oppositeend of which is seated against the adjacent end of the sleeve d5. Aplurality of resilient arms aresecured to the sleeve` 25 and eachcarries an inwardly projecting pin 32 received in suitable apertures 33provided in the wall of the barrel 2.

The member 2l is provided with cam faces 36- and 35, as best shown inFigures l and 12. When the cam surface 34 engages the free ends of thearms 3i, the elements 32 are thrust inwardly through the apertures 33 tofull choke position', as clearly illustrated. in Figures 12 and 13. Whenthus positioned, the sight gauge or pin it will be in engagement withthe opposite end of the slot i6, shown in Figure 9, in a manner similarto that shown and described with reference to Figures l to 8,

When the member 21 is rotated to cause the sight gauge or stop pin i6 toenter the relatively shorter slot i1V of the opening i5, theintermediatecam face te will engage the ends of the arms 3i and thereby onlypartially inwardly move the pins 321, whereby the gun isV provided witha. modified choke. When theI member 21 is in the position shown inFigures l0 and 1l, the resilient arms 3i are released sumciently topermit them to move the pins -32 completely out of the bore of thebarrel, whereby an open barrel is provided. y

A detent i8. similar to the one shown in Figure 8, is secured to themember 21 and is adapted to temporarily hold the member 21 in eitherfull or device modied, choke position until the gun is initially iired.When the gun is initially fired, the detent will move to its normalinoperative position, shown in Figure 14,'whereby the member 21 isreleased andy automatically moves or shifts from a modied or open barrelposition to the full choke position shown in Figuren. It will 'thus beseen that the operation of the attachment shown in Figures 9 to 14,inclusive, is similar to that described with reference to Figures 1Figure 15 illustrates another construction in which spherical elements3l are utilized in lieu of the disk-like elements and pins 32, shown inthe previous figures'. The operation of the form shown in Figure 15 issubstantlallyrthe sameas described with reference to the previousilgures.

'I'he novel choke attachment herein disclosed, has proven verysatisfactory and emcient in operation. When hunting small game, it isdesirable in most cases to use an open barrel for the ilrst shot, aswhen ilushing apheasant or some other upland game, because of therelatively short distance. If necessary to re a second shot, itis'usually desirable to use aV choked barrel because of the relativelygreater distance the charge must carry to hit its mark. As lhereinbeiorestated. by the use oi' this novel device, the bore of the gun isautomatically changed from open to full or modiiedchoke, when the gun isinitially tlred,-dependlng upon the pre-setting of the member 1, as therecoil ofthe gun automatically `effects the release of the device fromits non- -set for an open barrel, in which position it is retained untilthe next following shot, which will. again-eifect the automatic shiftingof the -device fromopen to modified .or full choke position.

The attachment is comparatively simple and inexpensive to manufactureand may readily be applied to conventional guns at small cost. It isvery compact and does not mar the appearance of the gun. and is soconstructed that the elements will have no e'ect upon the operationthereof. If desired, means not shown, may be provided for locking theattachment in open barrel position, whereby each shot fired from the gunwill be through an open barrel. In most cases. however, I have found itdesirable to use an open barrel for the ilrst shot and either a modifiedor full choke for succeeding shots. The attachment is so constructedthat it may readily be adjusted to provide the choke best suited foreach individual gun.

While 'I have herein shown the novel choke permanently xed to the gunbarrel, it is tobe understood that it may be made independently of thebarrel and removably secured thereto in the form of an attachment.

I claim as my invention:

, 1. A choke for a gun comprising means movable into and out of the boreof the gun barrel for varying the choke thereof, a member mounted forrelative movement on the barrel and adapted to relatively adjust saidchoke varying means, means for retaining said member in adiustedposition, and means, whereby the recoil of the gun will render saidretaining means ineffective and permit said memberto change from oneposition to another.

2. A choke for a gun comprising means movable into and out of thebore'of the gun barrel for varyrel, thereby, to

ing the choke thereof, a m relative movement orr'the barrel and 1:1'relatively shift said choke f i means open to choke position, me ior`noyretaining said mem in open pontion, d means whereby the recoil oi thegun will render said retaining means ineective and g .fm t the member toshift to choke position.

3. 'A choke for a gun comprising means movable into and out of the boreor the sun im; forA varying the choke thereof, a member mounted forrelative movement on the barrel and ada.- ito shift said choke varyingmeans from one position to another, a spring-actuated detent normal- VYl1y retaining the member in a predetermined posi'- tion, and meanswhereby the recoil oi the gun will render said detent ineffective andpermit the member to automatically shift fr one position to another whenthe is nred.

e. A choke for a l comprising a plurality of elements mov le into andout oi the bore oi the gun bei for vg the choke thereof, a membermounted for relative movement on the b and operatively with saidelements, a spring constantly ur the member into choke position, meansfor holding the member in non-choke tion, and ms whereby said holdingmeans is rendered ineffective to hold said member, when the gun isilred, whereby the spring will move the member to a modied or full choketion. 5. A choke for a barrel comprising a plurality of elements movableinto and .out of the bore of the gun barrel for varying the chokethereof, a member mounted for relative sliding movement on the barrel ina direction lengthwise thereof, said member being operatively associatedwith said elements, means for normally holding the member in a positionto provide a non-choke barrel, and means whereby said holding means isrendered ineiective to hold said member, when the gun is fired, wherebythe member is automatically moved from 'a non-choke to a, chokeposition.

6. A choke for a gun barrel comprising a plurality of elements movableinto and out of the bore of the gun barrel lor varying the chokethereof, a member mounted for relative movement on the barrel andconceali said elements, said mer being operatively associated with saidelements, a spring-actuated detent on said me ensageable with means edon the barhold the 1.-, r in non-choke position, and means whereby thetension in said detent will render the detent ineective to hold saidmember, when the gun is tired. and whereby the member is automaticallymoved from a nonchoke to a choke position.

7. An automatic choke for a gun barrel comprising a member mounted forrelative movement on the barrel, said barrel having a plurality ofapertures inthe wall thereof, elements loosely supported in saidapertures-and adapted to be partially projected therethrough into thebore of the barrel to provide a choke therefor, means on said member`adapted to engage and inwardly move 'said elements, when the member ismoved in one direction, and means for temporarily holding said into thebore oi the rrel. l

adapted to engage and inwardly move said elements, whenthe member ismovedin one direction, and means `for holding said member in nous-chokeposition, said means being rendered inoperative by the recoil of thegun, whereby the barrel is automatically changed from an open to amodiiied or full choke.

9. A choke for a gun barrel comprising an enlarged portion on the barrelhaving a plurality 0i apertures in the wall thereof communicating withthe bore of the barrel, a plurality ofelements loosely supported in saidapertures, a member fitting over saldenlarged portion and relativelymovable thereon to actuate said elements, a spring constantly urgingsaid member into a choke position, and a detent for holding said mem-Wber in non-choke position, said detent being adapted to release themember, when the gun is iired, whereby the member is automaticallyshifted to choke position.

10. A choke for a gun barrel comprising an enlarged portion on thebarrel having a plurality of apertures in the wall thereof, a pluralityof elements loosely supported in said apertures, a member tting oversaid enlarged portion and relatively movable thereon, said member havinga cam face adapted to actuate said elements, when moved in onedirection, thereby to partially project said elements into the bore ofthe barrel to provide a choke therefor, a spring constantly urging saidm'ember in a direction to force said elements into the bore of thebarrel, and resilient means manually operable to secure the member innon-choke position, said resilient means automatically becoming eiectiveto retain said member in non-choke position, when the gun is tired,whereby said member is automatically moved into choke position.

il. A choke for a gun barrel comprising an enlargement on the barrelhaving a plurality of elongated apertures therein communicating with4the bore of the gun, disk-like elements loosely supported in saidapertures, a member movably fitted over said enlargement and concealingthe disk-like elements supported therein, said member having a cam faceadapted to engage and move said elements into operative positions withinthe bore of the barrel, thereby to provide a choke for the gun, a springconstantly urging said member into choke position, and a spring-actuateddetent carried by said member and adapted to secure it in non-chokeposition, said springactuated detent being adapted to release saidmember, when the gun is ilred, whereby it will automatically move intova choke position.

l2. A choke for a gun comprising a plurality of resilient arms ilxed tothe barrel` and having projections thereon received in aperturesprovided in the wall of the barrel, said arms tending normally tosupport said projections in non-choke position, a member fitting overand concealing said arms and having means, adapted to engage said armsand move them inwardly, when said member is relatively moved in onedirection on the barrel, whereby said projections are extended into thebore of the barrel to provide a choke therefor.

13. A choke for a gun lcomprising a plurality of resilient arms disposedlengthwise of the barrel and each carrying an element, said barrelhaving a plurality of apertures in the wall thereof through which saidelements may be projected into the bore of the barrel, a member fittingover and concealing said arms, a spring constantly urging said member ina direction to actuate said 092,649 .arms and move the elements into thebore of the barrel, thereby to provide achoke therefor, and means fortemporarily locking said member in non-choke position and adapted, bythe recoil of the gun, to automatically release said member and permitit to return to a choke position.

14. A- choke for a gun comprising a plurality of resilient arms disposedlengthwise of the barrel and each carryingv an element, said barrelhaving a plurality of apertures in the Wall thereof through which saidelements may be projected into the bore of the barrel, a member ttedover and concealing said arms, a spring constantly urging said member ina direction to move said arms inwardly, whereby the elements carriedthereby are projected into the bore of the barrel to provide a choketherefor, and means for locking said member in non-choke position,comprising a spring-actuated detent secured to the member and adapted tobe moved into engagement with means on the barrel, thereby to secure themember in non-choke position.

15. A choke for a gun comprising a plurality of elements adapted to beprojected through apertures in the wall of the barrel to provide a chokethereor, spring means normally urging said elements into non-chokeposition, a member tted onto the barrel for actuating said elements, aspring constantly urging-said member into choke position, and means forlocking said member in non-choke position, comprising a detent adaptedto be manually moved in one direction to secure the member in nonfchokeposition and adapted, upon ring of the gun, to release said member andpermit it to return to a choke position.

` WALTER, M. JUNG.

